Reduced-pressure, linear wound closing bolsters and systems

ABSTRACT

A reduced-pressure, linear-wound closing bolster has a pivotable frame that moves from an extended position to a compressed position under the influence of reduced pressure. The closing bolster may have a first closing member, a second closing member, and an interior space. A manifold member is disposed within the interior space and may be coupled to the pivotable frame. When a reduced pressure is applied, the pivotable frame is urged from the extended position to the compressed position. A first gripping member for transmitting a closing force from the first closing member to a first edge of a linear wound may be attached. Likewise, a second gripping member for transmitting a closing force from the second closing member to a second edge of the linear wound may be attached. Systems and methods are also presented.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/050,182, filed Feb. 22, 2016 which is a continuation of U.S. patentapplication Ser. No. 13/954,703, filed Jul. 30, 2013, now U.S. Pat. No.9,295,587 which is a divisional application of U.S. patent applicationSer. No. 13/456,201, filed Apr. 25, 2012, now U.S. Pat. No. 8,523,832which is a divisional application of U.S. patent application Ser. No.12/475,388, filed May 29, 2009 now U.S. Pat. No. 8,187,237 which claimsthe benefit, under 35 USC § 119(e), of the filing of U.S. ProvisionalPatent Application Ser. No. 61/078,114, entitled “Reduced-Pressure,Linear-Wound Treatment System,” filed Jul. 3, 2008; and U.S. ProvisionalPatent Application Ser. No. 61/057,803, entitled “Reduced-Pressure,Linear Wound Closing Bolster and System,” filed May 30, 2008. All ofthese provisional applications are incorporated herein by reference forall purposes.

BACKGROUND

The present invention relates generally to medical treatment systems,and more particularly, to reduced-pressure, linear wound closingbolsters and systems.

Physicians perform millions of surgical procedures each year around theworld. Many of the procedures are performed as open surgery and anincreasing number are performed using minimally invasive surgery, suchas arthroscopic, laparoscopic, and endoscopic procedures. Howeverperformed, surgical procedures involve acute wounds, e.g., an incision,in the skin and related tissue. In many instances, the incision isclosed at the conclusion of the procedure using a mechanical apparatus,such as staples or sutures, and the wound is merely covered with a dry,sterile bandage.

The use of staples or sutures to close an acute wound may haveundesirable side effects. For example, staples and sutures can proximatethe wound edges tightly where they are applied, but in between suchmechanical closing devices are gaps or areas that are not as tightlyclosed. This may lead to areas of high stress proximate the closingdevice interspersed with areas of relatively low stress in between. Thismay, in turn, influence scarring, healing time, and strength of thewound.

BRIEF SUMMARY

Shortcomings with certain aspects of linear wound care are addressed bythe present invention as shown and described in a variety ofillustrative embodiments herein. “Linear wound” refers generally to alaceration or incision whether in a line or not. According to anillustrative embodiment, a reduced-pressure, linear-wound closingbolster for managing a linear wound includes a pivotable frame having afirst closing member, a second closing member, and an interior space.The pivotable frame is operable to move between an extended position anda contracted position. The closing bolster further includes a manifoldmember disposed within the interior space, a first gripping membercoupled to the first closing member, and a second gripping membercoupled to the second closing member. The first gripping member is fortransmitting a closing force from the first closing member to a firstedge of the linear wound. The second gripping member is for transmittinga closing force from the second closing member to a second edge of thelinear wound.

According to another illustrative embodiment, a reduced-pressure,linear-wound closing bolster includes a first closing member for placingon a first side of the linear wound, a second closing member for placingon a second side of the linear wound, and a first connecting member. Thebolster also includes a first pivot connector coupling a portion of thefirst closing member and the connecting member, a second pivot connectorcoupling a portion of the second member and the connecting member, and amanifold member coupled to an interior surface of the first closingmember and an interior surface of the second closing member. Themanifold member contracts when placed under a reduced pressure. Thebolster also includes an interface fluidly coupled to the manifold fordelivering a reduced pressure thereto.

According to another illustrative embodiment, a reduced-pressure, linearwound treatment system includes a closing bolster for placing on thepatient's skin over a linear wound and operable to move between anextended position and a compressed position. The closing bolstercomprises a pivotable frame having an interior space and a manifolddisposed within the interior space and coupled to the pivotable frame.The system includes a sealing subsystem for providing a fluid sealbetween the closing bolster and the patient, and a reduced-pressuresubsystem for delivering a reduced pressure to the sealing subsystem.The sealing subsystem and reduced-pressure subsystem are operable todeliver a reduced pressure to the closing bolster, and the closingbolster is operable under reduced pressure to go to the compressedposition and thereby develop an inward force.

According to one illustrative embodiment, a reduced-pressure,anisotropic closing bolster includes an anisotropic manifold memberoperable under reduced pressure to contract more in a lateral directionthan in a longitudinal direction. The anisotropic manifold memberincludes a plurality of longitudinal manifold members of a flexiblemanifold material, a plurality of reinforcing members, and ananisotropic bolster body formed by coupling the plurality oflongitudinal manifold members and the plurality of reinforcing members.The anisotropic bolster body is operable under reduced pressure tocontract more perpendicularly to the plurality of reinforcing membersthan parallel to the plurality of reinforcing members.

According to another illustrative embodiment, a method of applying aclosing force to a linear wound on a patient includes providing areduced-pressure, linear-wound closing bolster. Wherein thereduced-pressure, linear-wound closing bolster includes a manifoldmember and a pivotable frame that has an interior space and a firstclosing member and a second closing member. The first closing member hasa first longitudinal edge and a second longitudinal edge. The secondclosing member has first longitudinal edge and a second longitudinaledge. The method includes placing the second longitudinal edge of thefirst closing member proximate a first edge of the linear wound andplacing the second longitudinal edge of the second closing memberproximate a second edge of the linear wound. The method also includesforming a fluid seal between the pivotable frame and the patient's skin,coupling a reduced-pressure subsystem to an interface to the manifoldmember, and activating the reduced-pressure source.

According to another illustrative embodiment, a method of manufacturinga reduced-pressure, linear-wound closing bolster includes forming apivotable frame having first closing member, a second closing member,and an interior space, the pivotable frame operable to move between anextended position and a contracted position. The method includesdisposing a manifold member within the interior space and providing afirst gripping member operable to transmit a closing force from thefirst closing member to a first edge of a linear wound. The method alsoincludes providing a second gripping member operable to transmit aclosing force from the second closing member to a second edge of thelinear wound. The method may further include coupling the manifoldmember to the pivotable frame such that when a reduced pressure isapplied, the pivotable frame is urged from the extended position to thecontracted position.

According to one illustrative embodiment, a reduced-pressure,linear-wound closing bolster for managing a linear wound includes afirst closing member, a second closing member, a pivot connectorcoupling the first closing member and second closing member, and aninterior space formed at least in part by the first closing member andthe second closing member. The pivot connector is operable to movebetween an extended position and a compressed position. The closingbolster further includes a manifold member disposed within the interiorspace and coupled to the first closing member and second closing membersuch that when reduced pressure is applied, the pivotable frame is urgedfrom the extended position to the compressed position. The closingbolster also includes a first gripping member for transmitting a closingforce from the first closing member to a first edge of a linear woundand a second gripping member for transmitting a closing force from thesecond closing member to a second edge of the linear wound.

The illustrative embodiments may provide a number of advantages. Acouple of examples follow. Technical advantages of the illustrativeembodiments are perceived to include that the wound might be able towithstand more force during the healing process. Additionally, the woundedges that otherwise would not be tightly and smoothly approximated arehealed in a tight position with the edges approximated. The time for thewound to gain strength may be decreased. It may also reduce the scarformation at the wound. These are just some possible examples.

Other objects, features, and advantages of the illustrative embodimentswill become apparent with reference to the drawings and detaileddescription that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the method and apparatus of the presentinvention may be obtained by reference to the following DetailedDescription when taken in conjunction with the accompanying Drawingswherein:

FIG. 1 is a schematic, cross-sectional view of an illustrativeembodiment of a reduced-pressure, linear wound closing system;

FIG. 2 is a schematic detail of a first closure member of theillustrative embodiment of FIG. 1;

FIG. 3A is a schematic, cross-sectional view of an illustrativeembodiment of a reduced-pressure, linear wound closing bolster shown inan extended position;

FIG. 3B is a schematic, perspective view of the closing bolster of FIG.3A also shown in the extended position;

FIG. 3C is a schematic, cross-sectional view of the closing bolster ofFIGS. 3A and 3B shown in a compression position;

FIG. 4 is a schematic diagram showing one possible pattern for a dynamicreduced pressure delivered to a reduced-pressure, linear wound closuresystem;

FIG. 5 is a schematic, cross-sectional view of a linear wound showingthe development of collagen parallel to the closing force applied; and

FIG. 6 is a schematic, perspective view of another illustrativeembodiment of a closing bolster.

DETAILED DESCRIPTION

In the following detailed description of the illustrative embodiments,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration specific preferredembodiments in which the invention may be practiced. These embodimentsare described in sufficient detail to enable those skilled in the art topractice the invention, and it is understood that other embodiments maybe utilized and that logical structural, mechanical, electrical, andchemical changes may be made without departing from the spirit or scopeof the invention. To avoid detail not necessary to enable those skilledin the art to practice the invention, the description may omit certaininformation known to those skilled in the art. The following detaileddescription is, therefore, not to be taken in a limiting sense, and thescope of the present invention is defined only by the appended claims.

Referring to FIGS. 1 and 2 an illustrative embodiment of areduced-pressure linear wound closing system 100 for treating a linearwound 102, such as a laceration or, more typically, an incision 104 ispresented. Linear wound 102 has a first edge 106 and a second edge 108.While linear wound 102 may extend to different depths, it is shown as anincision 104 extending through epidermis 110, dermis 112, and intosubcutaneous tissue, or hypodermis, 114.

A dressing assembly 118 may be placed over the linear wound 102 and usedwith reduced pressure to supply an inward, or closing, force 120, and acompressive force 122 may be developed as well. Dressing assembly 118includes a closing bolster 126 that is moveable between an extendedposition (e.g., FIG. 1) and a compression position. A sealing subsystem178 provides a fluid seal between the dressing assembly 118 and thepatient's epidermis 110. A reduced-pressure subsystem 188 providesreduced pressure to an interior portion of the dressing assembly 118 andcauses the closing bolster 126 to be urged from the extended position tothe compressed position and thereby provides the inward, closing force124 to both edges 106, 108 of the linear wound 102.

Closing force 120 remains primarily within epidermis 110 and dermis 112.The closing force 120 may provide a smooth, tight approximation of edges106 and 108 of the linear wound 102. In addition, system 100 is operableto deliver a reduced pressure to incision 104 that may also be realizedat the level of any subcutaneous voids to help approximate—bringtogether—the tissues in that region as well as to help remove any air orany other fluids. The term “fluid” as used herein generally refers togas or liquid, but may also include any other flowable material. Adownward (for the orientation of FIG. 1) compression force 122 may alsobe developed.

The dressing assembly 118 may include closing bolster 126 and over-drape180. The closing bolster 126 may be formed in many ways and has theeffect of developing a closing force 120 when placed under reducedpressure. System 100 may further provide a compressive force 122, and atthe same time, manifold reduced pressure to the linear wound 102 forreduced-pressure treatment.

In the illustrative embodiment of FIG. 1, closing bolster 126 is formedwith a pivotable frame 130. To form the pivotable frame 130 of FIG. 1, afirst closing member 132, second closing member 146, and a connectionmember 160 are coupled as will be described. The members of pivotableframe 130 may be made of any material, e.g., a medical grade silicone.The members of the pivotable frame 130 may be extruded, pour molded,injection molded, blow molded, or formed by other manufacturingtechniques. The pivotable frame 130 is open on the ends (first end andsecond end, or proximal end and distal end) as the pivotable frame isdeployed on the epidermis 110 and over the linear wound 102, but iscovered by the over-drape 180 for use.

The first closing member 132 has a first longitudinal edge 134, secondlongitudinal edge 136, a first lateral edge (analogous to lateral edge238 in FIG. 3B), second lateral edge (analogous to lateral edge 240 inFIG. 3B), an interior surface 142, and a lateral axis 144 (FIG. 2).Similarly, the second closing member 146 has a first longitudinal edge148, second longitudinal edge 150, a first lateral edge (analogous tolateral edge 252 in FIG. 3B), second lateral edge (analogous to lateraledge 254 in FIG. 3B), an interior surface 156, and a lateral axisanalogous to axis 144 (FIG. 2). The connection member 160 has a firstlongitudinal edge 162, a second longitudinal edge 164, a first lateraledge (analogous to first lateral edge 266 in FIG. 3B), and a secondlateral edge (analogous to second lateral edge 268 in FIG. 3B).

The first longitudinal edge 134 of the first closing member 132 ispivotably coupled by a first pivot connector 170 to the firstlongitudinal edge 162 of the connection member 160. The firstlongitudinal edge 148 of the second closing member 146 is pivotablycoupled by a second pivot connector 172 to the second longitudinal edge164 of the connection member 160. Together, the pivotably coupled firstclosing member 132, second closing member 146, and connection member 160form the pivotable frame 130 and further defines an interior space 174.In one variation, the pivotable frame 130 may be formed by using a firstpivot connector to couple the first longitudinal edge 134 of the firstclosing member 132 to the first longitudinal edge 148 of the secondclosing member 146.

The first pivot connector 170 may be any device or system that holds thefirst longitudinal edge 134 of the first closing member 132 to the firstlongitudinal edge 162 of the connection member 160 (or firstlongitudinal edge 143 of the second closing member 146) and allowsrelative movement. The first pivot connector 170 may be, for example, apiano hinge, a living hinge, butterfly hinge, strap hinge, afilament-tape connection, tape, etc. The pivot connector 170 may also bea relief in a sheet of material that allows the sheet to fold and bendalong an edge. The other connectors herein, e.g., connector 172, mayalso be any type of connector, such as those referenced in thisparagraph.

A first gripping member 145 may be associated with the secondlongitudinal edge 136 of the first closing member 132, and a secondgripping member 159 may be associated with the second longitudinal edge150 of the second closing member 146. The gripping member 145, 159 maybe a first adhesive strip 147 and a second adhesive strip 161,respectively. Alternatively, the edges 136, 150 may have high-frictionmembers, e.g., soft silicone, added that are able to provide a frictioninterface with the skin such that as the edges 136, 150 are moved theskin moves with the edges 136, 150 without any significant slippingtherebetween. The gripping member 145 and 159 are operable to transmitthe inward, closing forces 120 from the closing members 132 and 146 tothe patient's skin and thereby urge the edges 106 and 108 of the linearwound 102 into close approximation.

A manifold member 175 is disposed within the interior space 174 of thepivotable frame 130 and may be coupled to the interior surface 142 offirst closing member 132 and to the interior surface 156 of secondclosing member 146. In an alternative embodiment, the manifold member175 may not be coupled to the interior space 174 and reduced pressuremay primarily move the first closing member 132 and second closingmember 146 towards each other. The manifold member 175 contracts whenplaced under reduced pressure and is operable to distribute a reducedpressure to the linear wound 102. The manifold member 175 may be madefrom many possible manifold materials.

The term “manifold” as used herein as a noun generally refers to asubstance or structure that is provided to assist in applying reducedpressure to, delivering fluids to, or removing fluids from a tissuesite. In one illustrative embodiment, the manifold member 175 is madefrom a porous and permeable foam-like material and, more particularly, areticulated, open-cell polyurethane or polyether foam that allows goodpermeability of wound fluids while under a reduced pressure. One suchfoam material that has been used is the VAC® Granufoam® Dressingavailable from Kinetic Concepts Inc. (KCI) of San Antonio, Tex. Anymaterial or combination of materials might be used for the bolstermaterial provided that the bolster material is operable to manifold thereduced pressure and contract under reduced pressure. A manifoldtypically includes a plurality of flow channels or pathways that areinterconnected to improve distribution of fluids provided to and removedfrom the area of tissue around the manifold. Examples of manifolds mayinclude without limitation devices that have structural elementsarranged to form flow channels, cellular foam such as open-cell foam,porous tissue collections, and liquids, gels and foams that include orcure to include flow channels. The bolster material might also be acombination or layering of materials; for example, a first bolster layerof hydrophilic foam might be disposed adjacent to a second bolster layerof hydrophobic foam to form the bolster material.

The reticulated pores of the Granufoam® material, that are in the rangeof about 400 to 600 microns, are helpful in carrying out the manifoldfunction, but other materials may be used. A material with a higherdensity (smaller pore size) than Granufoam® material may be desirable insome situations. The manifold member 175 may be a reticulated foam thatis later felted to a thickness of about ⅓ the manifold member's 175original thickness. Among the many possible materials, the followingmight be used: Granufoam® material or a Foamex technical foam(www.foamex.com). In some instances it may be desirable to add ionicsilver to the foam in a microbonding process or to add other substancesto the manifold member 175 such as antimicrobial agents. The manifoldmember 175 may be isotropic or anisotropic depending on the exactorientation of the forces 120, 122 that are desired during reducedpressure. The manifold member 175 could also be a bio-absorbablematerial.

Sealing subsystem 178 may include an over-drape 180, or drape, which hasa first side 181 and a second side 182. The over-drape 180 covers thedressing 118 and extends past a peripheral edge 176 of bolster 126 toform a drape extension 183. Drape extension 183 has a first side 184 anda second side 185. A sealing apparatus 186 may be used to seal the drapeextension 183 to the patient. Sealing apparatus 186 may take numerousforms, such as an adhesive sealing tape 187, or drape tape or strip;double-side drape tape; adhesive; paste; hydrocolloid; hydrogel; orother sealing device. If a tape 187 is used, the tape 187 may be formedof the same material as the over-drape 180 with a pre-applied,pressure-sensitive adhesive on the second side 185 of the extension 183.An adhesive might also be used to provide a substantially fluid sealbetween the over-drape 180 and the epidermis 110 of the patient. Beforethe over-drape 180 is applied to the patient, the adhesive may haveremovable strips covering the adhesive removed, or the drape 180 may beapplied and the tape 187 placed to form a seal.

Over-drape 180 may be an elastomeric material that has pore sizes lessthan about 20 microns. “Elastomeric” means having the properties of anelastomer and generally refers to a polymeric material that hasrubber-like properties. More specifically, most elastomers haveelongation rates greater than 100% and a significant amount ofresilience. The resilience of a material refers to the material'sability to recover from an elastic deformation. Examples of elastomersmay include, but are not limited to, natural rubbers, polyisoprene,styrene butadiene rubber, chloroprene rubber, polybutadiene, nitrilerubber, butyl rubber, ethylene propylene rubber, ethylene propylenediene monomer, chlorosulfonated polyethylene, polysulfide rubber,polyurethane, EVA film, co-polyester, and silicones. Over-drapematerials may include a silicone, 3M Tegaderm® drape material, acrylicdrape material such as one available from Avery, or an incise drapematerial.

The over-drape 180 may or may not be coupled to the bolster 126. Ifcoupled, the coupling may occur in many ways. Over-drape 180 and bolster126 may be coupled using adhesives such as an acrylic adhesive, siliconeadhesive, hydrogel, hydrocolloid, etc. Over-drape 180 and bolster 126may be bonded by heat bonding, ultrasonic bonding, and radio frequencybonding, etc. The coupling may occur in patterns or more completely.Structure might be added to the bond to make the over-drape 180 behaveanisotropically in a desired direction, i.e. to make an anisotropicdrape material. An anisotropic drape material helps the dressingassembly 118 to primarily move in a given direction, i.e. only about acertain axis or axes. This may be particularly useful in a closingapplication.

Reduced-pressure subsystem 188 includes a reduced-pressure source 189,which can take many different forms. Reduced-pressure source 189provides a reduced pressure as a part of system 100. The term “reducedpressure” as used herein generally refers to a pressure less than theambient pressure at a tissue site that is being subjected to treatment.In most cases, this reduced pressure will be less than the atmosphericpressure at which the patient is located. Alternatively, the reducedpressure may be less than a hydrostatic pressure of tissue at the tissuesite. It is often desirable for the reduced-pressure source 189 todevelop a continuous reduced pressure below atmospheric pressure andalso to be able to deliver a dynamic pressure, i.e., to vary the reducedpressure in a cycle or operate in a continuous or intermittent mode. Theoperable range of reduced pressure may vary widely as needed, but wouldtypically include 200 mm Hg below atmospheric. In order to maximizepatient mobility and ease, reduced-pressure source 189 may be abattery-powered, single-use reduced-pressure generator. Such a pressuresource 189 facilitates application in the operating room and providesmobility and convenience for the patient during the rehabilitationphase.

In the illustrative embodiment of FIG. 1, the reduced-pressure source189 is shown having a battery compartment 195 and a canister region 190with windows 191 providing a visual indication of the level of fluidwithin canister 190. An interposed membrane filter, such as hydrophobicor oleophobic filter, might be interspersed between a conduit, ortubing, 192 and the reduced-pressure source 189.

The reduced pressure developed by reduced-pressure source 189 isdelivered through the delivery tube or conduit 192 to an interface 193,which might be an elbow port 194. In one illustrative embodiment, port194 is a TRAC® technology port available from KCI of San Antonio, Tex.Interface 193 allows the reduced pressure to be delivered to the sealingsubsystem 178 and received by the manifold member 175.

In the embodiment of FIGS. 1 and 2, application of reduced pressure fromthe reduced-pressure subsystem 188 causes the manifold member 175 tocontract inward, but because overdrape 180 surrounds the pivotal frame130, there is also a downward (for the orientation shown) force placedon the pivotal frame 130. In this particular embodiment, it is desirableto orient the members of the pivotal frame 130 so that the downwardforce will be translated into a contribution to the closing force 120.As shown in FIG. 2, this may be accomplished by placing the closingmembers 132 and 146 with an inward orientation. For example, firstclosing member 132 is shown in cross-section having a lateral axis 144that makes an angle α with a reference line or axis 143 that is normalto epidermis 110. Thus, the inward angle α means that as a force isapplied downward on connection member 160, the force will urge firstmember 132 to pivot about first pivot connection 170 and want tocollapse inward. This helps to urge the epidermis 110 in the directionof the linear wound 102.

In operation, reduced-pressure, linear wound closing system 100 may beapplied to further assist mechanical closure devices such as sutures orstaples already applied, or may be the only and primary closing sourcefor linear wound 102. In either case, the system 100 is applied byplacing the first closing member 132 on first wound edge 106 and thesecond closing member 146 on the second wound edge 108. Gripping member145 on second longitudinal edge 136 is used to engage first edge 106 ofthe wound 102. In the particular embodiment shown, the first grippingmember 145 is an adhesive strip 147. Thus, the healthcare provider wouldremove visible backing from the adhesive strip 147 and the adhesivestrip 147 would be applied proximate first edge 106. In a similarmanner, the second gripping member 159 in this embodiment is an adhesivestrip 161, and a backing may be removed and the strip 161 appliedproximate the second edge 108 of the linear wound 102. Adhesive strips147 and 161 are applied near edges 106 and 108 in a manner that placesthe closing members 132 and 146 at an inward angle as described earlierin connection with FIG. 2. It should be noted that in this particularembodiment, the manifold member 175 has already been placed withininterior space 174 formed by the pivotal frame 130, but in otherapplications the manifold member 175 could be inserted just prior toapplying the gripping members 145 and 159 to the epidermis 110. If theoverdrape 180 has not already been coupled to an exterior surface of thepivotable frame 130, the overdrape 180 is then placed over the frame 130and caused to extend beyond the peripheral edges 170 to form the drapeextensions 183. In this particular embodiment, adhesive tape 187 is thenapplied to make sure a fluid seal is formed between drape 180 and thepatient's epidermis 110. Reduced-pressure interface 193 is applied andis coupled to delivery tube 192, which in turn is coupled to thereduced-pressure source 189.

Reduced-pressure source 189 may then be activated to deliver reducedpressure to the sealing subsystem 178 and in particular to the manifoldmember 175. Subject to reduced pressure, manifold member 175 contractsand is compressed down along with the pivotal frame 130. The combinationof forces urges the second lateral edges 140 and 154 towards each otherand towards wound 102, provides some compression force down, andmanifolds reduced pressure to the wound 102.

Referring to FIGS. 3A, 3B, and 3C, another embodiment of areduced-pressure, linear-wound closure system 200 is presented. Many ofthe parts are analogous to those of system 100 of FIGS. 1 and 2 and thepossible relationship presented as such by simply indexing the numbersby 100. Referring particularly to FIG. 3A, two particular differencesare noted. First, the sealing subsystem 278 does not involve the use ofan overdrape, but provides a pivotable frame 230 to which a first endcap 263 (FIG. 3B) and a second end cap 265 (FIG. 3B) have been added toform a fluid seal. The interface 293 allows reduced pressure to besupplied to the manifold member 275 without compromising the fluid seal.Second, in application, the closing members 232 and 246 may be allowedto have an outward angle relative to reference line normal to theepidermis (analogous to reference line 143 of FIG. 2). This is becausein this embodiment there will not generally be a downward compressionforce placed on the pivotable frame 230. The closing members 232 and 246are urged together to provide the inward force 220 primarily bycontraction of the manifold member 275. The application of reducedpressure to the manifold member 275 causes the closing bolster 226 tomove from an extended position shown in FIGS. 3A and 3B to a compressionposition shown in FIG. 3C.

Referring to FIG. 3B, system 200 includes pivotal frame 130, which isshown positioned with a lengthwise dimension running parallel to woundaxis 203 of linear wound 202. Linear wound 202 has first edge 206 andsecond edge 208. The first closing member 232 has first lateral edge 238and a first longitudinal edge 234. The second closing member 246 has afirst lateral edge 252 and a second lateral edge 254. The second closingmember 246 also has first longitudinal edge 248 and second longitudinaledge 250.

End caps 263 and 265 may be formed in a number of different ways toprovide a fluid seal to the ends of the pivotal frame 130. In thisparticular embodiment, they are shown as adhesive portions of anoverdrape material that have been applied to cover the end pieces.

In systems 100 and 200, the reduced pressure delivered by reducedpressure subsystems 188 and 288 may be supplied in a continuous mode ora dynamic reduced pressure mode. In a dynamic mode, the pressure isvaried in any number of different types of patterns. For example,referring to FIG. 4, one particular pattern for the application ofreduced pressure is presented. The ordinate axis 310 gives the reducedpressure. It should be understood that an increase in reduced pressurehere means that a lower gauge pressure would be shown. The abscissa axis312 gives the elapsed time. Thus, in this particular pattern, thereduced pressure is ramped up to a baseline level 314 and then varied,in this instance, in a sinusoidal pattern between a greater reducedpressure level 316 and a lower reduced pressure 318. This variation inreduced pressure causes micromotion of the wound by varying the closingforces, e.g., the variation of the closing forces 120 and 220 of theembodiments of FIG. 1 and FIG. 3.

Referring now to FIG. 5, one of the beneficial effects encouraged by useof the dynamic pressure, such as the illustration given in connectionwith FIG. 4, is presented. A linear wound 402 through epidermis 410,dermis 412, and even into subcutaneous tissue 414 is shown. Linear wound402 has been subjected to dynamic micromotion for forces 420 which mayhave been generated by a system such as system 100 or system 200, FIG. 1and FIG. 3, respectively. The micromotion causes the collagen 416 to bedeposited in the wound 402 with an orientation that is parallel to theforces 420.

Referring now to FIG. 6, another embodiment of a system for providing aclosing force to a linear wound is presented. In this system, ananisotropic bolster 526 is formed with an anisotropic body 528. Theanisotropic body 528 comprises an anisotropic manifold member operableunder reduced pressure to contract more in a lateral direction, i.e.,parallel to force 520, than in a longitudinal, or lengthwise, direction,i.e., perpendicular to force 520.

The anisotropic body may be formed in many ways. As one illustrativeembodiment, the bolster body 528 may be formed by utilizing a pluralityof flexible, or compressible, manifold members 530 and a plurality ofreinforcing longitudinal members 532. The plurality of flexible manifoldmembers 530 may be analogous to the material from which manifold members175 and 275 were made in previously described embodiments. Thereinforcing longitudinal members 532 are formed of a material, orreinforcing material, that inhibits compression along one or more axesor directions. The reinforcing material may also inhibit expansion alongone or more axes. The reinforcing material may inhibit both compressionand expansion along one or more axes or directions. In one illustrativeembodiment, the reinforcing longitudinal members 532 are filamentscombined with the manifold members 530 to form the bolster body 528. Itwill be appreciated that for the orientation shown, the resultinganisotropic bolster body 528 will be able to contract or compress in afirst direction 534, but not in a substantial way in a second direction536.

In operation, the anisotropic closing bolster 526 will be placed down ona linear wound with the lengthwise dimension of the plurality ofreinforcing members 532 running parallel to the wound, i.e., with thelinear wound substantially parallel to direction 536. An overdrapeanalogous to drape 180 of system 100 may be applied over the bolster 526and an interface, which is analogous to interface 193 of FIG. 1, may beapplied in order to deliver reduced pressure. When reduced pressure isdelivered to the anisotropic closing bolster 526, it will contract inthe first direction 534 and this causes inward forces 520 to be directedon both edges of the wound, providing a closing force. The reducedpressure supplied to anisotropic bolster 526 may be dynamically variedas previously discussed or provided in a constant mode.

It should be apparent from the foregoing that an invention havingsignificant advantages has been provided. While the invention is shownin only a few of its forms, it is not just limited but is susceptible tovarious changes and modifications without departing from the spiritthereof.

I claim:
 1. An apparatus for providing reduced pressure to treat awound, comprising: a bolster body adapted to be positioned on the woundand to apply a closing force in a first direction across opposing sidesof the wound, the bolster body comprising: a plurality of manifoldmembers adapted to compress and to distribute reduced pressure to thewound when the bolster body is exposed to reduced pressure, and aplurality of filaments combined with the manifold members and adapted toinhibit compression in a second direction orthogonal to the firstdirection; and an over-drape adapted to cover the bolster body and thewound to form an internal space for receiving reduced pressure; whereinthe bolster body is adapted to contract in the first direction to applythe closing force on the wound when reduced pressure is applied to theinternal space.
 2. The apparatus of claim 1, wherein the manifoldmembers are formed from a porous material.
 3. The apparatus of claim 1,wherein the manifold members comprise an open-cell foam material.
 4. Theapparatus of claim 3, wherein the open-cell foam material has a poresize in the range of about 400 μm to about 600 μm.
 5. The apparatus ofclaim 1, wherein the manifold members comprise an open-cell,polyurethane foam material.
 6. The apparatus of claim 1, wherein themanifold members comprise an open-cell, polyether foam material.
 7. Theapparatus of claim 1, wherein the manifold members comprise a layer ofhydrophilic foam and a layer of hydrophobic foam.
 8. The apparatus ofclaim 1, wherein the manifold members include a plurality of flowchannels to facilitate the distribution of reduced pressure.
 9. Theapparatus of claim 1, wherein the manifold members are formed from anisotropic material.
 10. The apparatus of claim 1, wherein the filamentsare substantially non-compressive in a third direction orthogonal to thefirst direction and the second direction and adapted to inhibitcompression of the bolster body in the third direction.
 11. Theapparatus of claim 1, wherein the filaments are substantiallycompressive in a third direction orthogonal to the first direction andthe second direction, and wherein the bolster body is adapted to apply acompressive force to the wound in the third direction when reducedpressure is applied to the internal space.
 12. The apparatus of claim 1,wherein the manifold members comprise a single manifold and thefilaments are disposed substantially in parallel within the singlemanifold to form the bolster body.
 13. The apparatus of claim 1, whereinthe manifold members comprise manifold layers and the filaments aredisposed substantially in parallel within the manifold members to formthe bolster body.
 14. The apparatus of claim 1, wherein the plurality offilaments are substantially non-compressive and adapted to reinforce themanifold members.
 15. The apparatus of claim 1, wherein the plurality offilaments are coupled to the manifold members.
 16. The apparatus ofclaim 1, wherein the filaments are adapted to be positionedsubstantially parallel to the opposing sides of the wound and the seconddirection.
 17. An apparatus for providing reduced pressure and a closingforce to treat a wound, comprising: a bolster body adapted to bepositioned on the wound and comprising: at least one manifold memberadapted to distribute reduced pressure and to compress in at least afirst direction orthogonal to opposing sides of the wound, and at leastone filament combined with the manifold member and adapted to inhibitcompression of bolster body in at least a second direction orthogonal tothe first direction; and an over-drape adapted to cover the bolster bodyand the wound to form an internal space for receiving reduced pressure;wherein the bolster body is adapted to contract in the first directionto apply the closing force and to distribute reduced pressure whenreduced pressure is applied to the internal space.
 18. The apparatus ofclaim 17, wherein the at least one filament is substantiallynon-compressive and adapted to reinforce the at least one manifoldmember.
 19. The apparatus of claim 17, wherein the at least one filamentis coupled to the at least one manifold member.
 20. The apparatus ofclaim 17, wherein the at least one filament is adapted to be positionedsubstantially parallel to the opposing sides of the wound and the seconddirection.